Cabletron Systems SmartSwitch Router, User'S Reference Manual

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SmartSwitch Router User Reference Manual 213
Chapter 13: IP Policy-Based Forwarding Configuration Guide
To set the IP policy action with respect to dynamic or statically configured routes, enter
one of the following commands in Configure mode:
Checking the Availability of Next-hop Gateways
The SSR can check the availability of next-hop gateways by querying them with
ICMP_ECHO_REQUESTS. Only gateways that respond to these requests are used for
forwarding packets. To configure the SSR to do this, enter the following command in
Configure mode:
Note: Some hosts may have disabled responding to ICMP_ECHO packets. Make sure
each next-hop gateway can respond to ICMP_ECHO packets before using this
option.
Applying an IP Policy to an Interface
After you define the IP policy, it must be applied to an inbound IP interface. Once the IP
policy is applied to the interface, packets start being forwarded according to the IP policy.
Cause packets matching the
profile to use the IP policy route
first. If the next-hop gateway is
not reachable, use the dynamic
route instead. ip-policy
<name>
permit acl
<profile>
action
policy-first
Route packets matching the
profile using dynamic routes
first. If a dynamic route is not
available, then route packets
matching the profile using the IP
policy gateway. ip-policy
<name>
permit acl
<profile>
action
policy-last
Cause packets matching the
profile to use the IP policy route.
If the next-hop gateway is not
reachable, then drop the packets. ip-policy
<name>
permit acl
<profile>
action
policy-only
Drop packets matching the
profile. ip-policy
<name>
permit acl
<profile>
next-
hop-list null
Drop packets that do not match
any profile. ip-policy
<name>
permit everything-else
next-hop-list null
Periodically check the
availability of next-hop
gateways. ip-policy
<name>
set pinger on